Crossed Over
by Rigorin
Summary: It's a battle between Shana (Shakugan No Shana) and Sieg Wahrheit (Chaos Legion). So read it and stuff. Take note I wrote this at night for a higher word output and then proofread it in the morning to see if it would turn out okay, so don't go expecting much out of an experiment. Personally, I feel kind of meh with the end result. Rated T cause I don't know how ratings work.


**Yeah whatever I don't own this and I'm not too good at writing and I haven't done things and stuff in a while and stuff JUST READ THE FIC it took me forever to write this thing**

* * *

From the moment she awoke, the fiery-haired girl knew something was wrong.

Her suspicions were only confirmed when she sat up to observe her surroundings.

On all sides, walls made of heavy stone blocks piled upon one another stretched up into the sky. When her eyes focused in, she realized they weren't actually tall enough to reach the clouds, but they were still high enough to give one the feeling of being trapped despite having open sky stretching out above them.

She scoffed at the lack of a ceiling. Maybe that once would have held her, but her ability to fly had long outclassed such petty obstacles. Since she wasn't boxed in, the walls were no more than hurdles to jump over in her eyes. Whoever had placed her there might as well have tried to imprison her in a cell made of Styrofoam.

Seeing no reason to remain where she was any longer, Shana prepared to extend a set of wings and take off so she could find out exactly where she was.

However, something made her hesitate.

That something was a voice.

"I wouldn't suggest trying that."

That voice made her freeze up, like a deer caught in the headlights.

"I'll stop you in an instant."

It wasn't as if she knew the voice, or anything dramatic like that.

"I'm afraid you won't be leaving here that easily."

The voice was simply so filled with hostility, so overflowing with killer intent that the runoff surrounded her and forced her to hold still.

"Sorry to inconvenience you, but you'll be my opponent today."

Shana finally managed to regain control of her body, and she spun to face the voice. Standing there was a tall man with hair a darker red than her own. His outside appearance made him look holy, like a man of God or some sort of crusader, but something was wrong with him. It was as if some form of corruption has infected him, had dug into his very core, eaten away at his mind and driven him insane.

In other words, although he may once have been a good man, it seemed at the time that all he knew was battle.

It was only then, as she faced the man who was oozing with murderous intentions, that Shana realized how large the area she was enclosed in truly was.

It was a huge arena, the kind of arena used to hold fights between gladiators. The stands were withered and ruined, and vines had grown into every nook and cranny, but despite that the place could be said to be in decent condition. It seemed stable, and it certainly wasn't about to collapse. At the very least, it was still suitable for a fight.

The man started to move, and Shana's vision focused back in on her opponent. She mentally cursed at herself for pulling her attention away from an enemy like that.

"You... what's your name?" asked the fiery-haired girl as her hand grabbed the handle of the sword resting against her hip.

"Sieg," the man replied without hesitation. "My name is... my name was Sieg Wahrheit, but it hardly matters now," he continued as he brought a hand from behind his back, revealing his own blade. "Especially since you're going to be dying here anyway."

Shana glared at the man as he approached. Although he appeared to be moving casually, the man had no openings. His guard was up; the moment she attacked, he would counter. Being a skilled fighter herself, Shana was too smart to merely walk into an attack like that.

The two stared each other down. Shana held still in a defensive stance while the man slowly moved closer.

Suddenly, alarms blared in Shana's head.

The battle had officially begun.

Shana kicked off of the ground and swung to the side as a blade stabbed through the spot she was in, cutting loose a few strands of her hair as it passed.

Yet the man had not been close enough to attack her himself. She doubted anyone could move so quickly without changing their posture even just a little bit beforehand, yet a blade had attacked her from outside his range.

"How...?"

And then she saw the answer.

The man himself had not attacked her; rather, a life-sized, knight-like marionette had shot from him like a crude clone and assaulted her at high speed.

The moment Shana realized this, she noticed several others surrounding the man in a circle. They darted out in her direction, not just one but five, moving to seal her escape and attack her from a ring.

By sheer reflex, her counter was simple.

As though set off by an invisible spark, a flame ignited on the ground before her. Within half a second the flame expanded and engulfed every single one of the doll-like creatures, burning them to ash and leaving no trace behind.

However, the man's attack wasn't over yet. All he had done thus far was the equivalent of reaching out and tapping her cheek.

Almost immediately afterward, a shockwave blew away the smoke that had curled up around her. The first was quickly followed by a second and third in an attempt to knock the girl off balance. Seeing the intent behind those attacks, Shana used her fire like a high-powered booster to shoot herself backwards out of range. She used that moment of peace to observe her enemies.

Attacking her now was a gang of large orc-like golems, floating on weak wisps of flame as if to insult gravity itself.

"What are these...?" Shana asked as she took a moment to breathe.

"Oh, you're interested?" asked the man. "These are my Legions. They don't play around and they aren't stupid, so don't fail to take them seriously."

After that half-assed explanation was given, the man replaced said golems with another set of the knight-like creatures.

"I've been holding back to see how strong you are, and it seems you're rather pathetic. Only that small fight and you're already out of breath? Let's see how long you can run for your life."

The creatures flew at her again, but this time they were even faster. They broke the sound barrier in half a second and surrounded Shana within a broad ring, this time taking stance just out of her practical attack range.

Her flame was strong, but it was strongest when it was close to her. Killing them at that distance would be significantly more difficult than if they had kept the ring tight.

"Of course, I can only summon so many Legions in a single fight, but considering you've killed but a few in a full minute of combat, I'm willing to bet my life that you won't be able to stay alive until  
I run out."

The knights primed their blades and began their attack. Just as the man had said, they were no longer playing games.

One by one, the Legions shot into the ring, slashing at Shana and then darting back out to the edge. Barely able to avoid, Shana swung herself out of the way of every attack, letting out a burst of flame each time in an attempt to roast the knights as they passed. It was of little use. The knights completed their attack pattern three times without suffering much more than an occasional burn.

Attacking them as they came wouldn't work, and Shana was slowly losing stamina. The Legions were simply too quick to fight like that.

But Shana was not an amateur. If her tactic didn't work, she would switch her combat pattern to something more effective.

As if waiting for her to make a move, the knights held still for a short few seconds, giving Shana just enough time to take a breath before she began her attack.

Using her intense flame as a booster, Shana shot herself to the edge of the ring as quickly as she could and attacked one of the knights with her sword. The allowed the blade to cut it in half, not reacting to her attack even as it fell to ground in pieces and vanished. Although it was quickly replaced by another, the Legions couldn't possibly last forever. Now that Shana had found a tactic to fight them with, it was only a matter of time.

She continued to use the same pattern to slice through each of the knights, allowing them not a single attack in between her own.

"The problem with your Legions," Shana said as she sliced through yet another of the knights, "is that they're predictable. They're like a simple AI. They react the same way to every situation, so they never learn how to fight an opponent who has a method of dealing with them."

Sieg merely watched as Shana continued to destroy his knights one after another.

"So long as I can keep slicing these things to pieces, I'll easily beat you!"

As if to punctuate her statement, Shana kicked off away from the knights and swung her blade directly at Sieg.

Waiting for him to run out of Legions was a waste of time, she'd decided. The fiery-haired girl had confidence that she could defeat him before even that.

However... Shana's attack held enough power to kill, yet the man didn't so much as flinch.

As if dropping a coat that made it invisible, a golem appeared between the two. In a haste to dodge its inevitable shockwave, Shana quickly stopped her momentum and boosted backwards away from the man. At a safe distance, she caught her breath while making sure she wasn't in any immediate danger.

Her opponents again took the form of golems, but she had a tactic for fighting those monsters as well.

The golem-like Legions were slow and couldn't attack very quickly, so the time between each shockwave was delayed. Shana used this small window of vulnerability to accurately dash in and slice each golem into pieces. In this manner, Sieg's first set of golems was reduced to nothing in mere seconds. Even as they were replaced, the Legions only grew weaker. Sieg could only counterattack for so long before Shana's constant overall power became greater than his quickly plummeting combat ability.

This was her tactic. This was how Shana would claim victory.

But Sieg was hardly worried. As a matter of fact, a smile began to slowly creep its way across his now-twisted face.

"It seems you can counter each of my Legions. I suppose even if I used several different ones, you would develop new attack patterns for all of them. But how well can you keep up if I simply decide to shake things up a little?"

The golems disappeared and were instantly replaced by several new, bow-wielding Legions.

Their aiming speed was incredibly fast, and their accuracy was deadly. With no measurable delay, the group of Legions spun to aim at the flame-haired girl and began firing at Shana's quickly-moving form using strange bolts made of some sort of energy.

The shots moved too quickly for the girl to dodge. From what she could see, the arrows would hit her in between movements. For this reason, rather than dodging, Shana reflexively brought a wall of fire up before her.

The arrows stood no ground to her intense flame. They burned up before getting anywhere close to hitting her.

Seeing this, Shana intensified the flame wall and boosted out towards each of the archers, intending to slice them apart one by one. Though they spread out to make it harder for her to destroy them, the archer's shots were useless against Shana, thus their wasted effort only delayed the inevitable.

For a moment, Shana considered Sieg to be a somewhat weak opponent. His only real strength laid in his Legions, which were relatively simple to predict and counter.

However, she was quickly proven wrong.

As predictable as his Legions were, they worked well if used properly.

And nobody knew how to use the Legions better than Sieg.

Shana dashed in towards one of the archers to attack it, but as she was closing in, the archer vanished. Almost instantaneously, a golem materialized in its place.

There was barely time to dodge.

Although Shana did successfully boost away from the attack, the edge of the shockwave had thrown her slightly off balance. In that small opening, a ring of archers appeared, formed around her and fired simultaneously.

Of course, none of them hit. The moment they attacked, Shana simply used an intense sphere of flame to destroy the arrows midair.

But as soon as the arrows burned up, the archers became knights, which immediately attempted to attack her all at once.

Shana was trapped. Even if she ran, she would only be countered again.

"_Not good..._" she thought.

The knights were closing in. There was only one way out.

"I'll fly."

Without even a split second to spare, the fiery-haired girl shot up into the sky on wings of flame, burning some of the knights to ashes as she flew off.

Now was the time to attack, she decided. Shana's opponent had no more cards to play. Her sword began to glow a deep reddish-orange, charging itself with enough power to kill the strongest of enemies in one strike.

Even if he shot at her, the arrows would merely burn up in the air. Even if he used golems, she would slice right through them, unaffected by their ground-based attacks. Even if he used knights, she would destroy them as she closed in. Even if he blocked or dodged, the excess power expanding from her sword would be more than enough to kill him.

This was checkmate.

However...

"That's just stupid."

Shana had been flying directly towards Sieg, hovering just over the ground as she approached the sound barrier, but something had stopped her.

More accurately, something had come up and grabbed her with such force that it halted her movement right then and there.

"You should know to always assume your opponent has more tricks up their sleeve."

The force that had stopped her was a metal, claw-like Legion.

Its grip was painful, but the rest of Sieg's attack was worse. Shana was so surprised by her sudden stop that she didn't even think to destroy the claw.

With an incredibly fast spin that tore at the joints in Shana's body, the claw flung her forwards across the ground. Though she landed on her feet, the high velocity caused her to stumble off-balance as she attempted to stop her momentum. However, before she could regain her stability, Shana heard a strange, high-pitched sound from her side.

A Legion resembling a shield was charging a cannon at her.

It was going to hit her at point-blank range.

Using the little reaction time she had, Shana shot herself off to the side. The cannon fired at that exact moment, singeing bits of her clothing with some unknown energy.

There was no longer any hope for victory.

From the moment the claw had gotten a hold of Shana, the battle had already been decided.

While still off balance, Shana was attacked by a ring of archers. She countered using another flame sphere, but in that moment of distraction she was attacked by another barrage of knights. Barely able to dash out to the side, Shana fell within the range of a newly summoned golem.

Her opponent could not use different kinds of Legions at a time.

But he could switch between so quickly that such a limitation hardly mattered.

By overwhelming her with pure speed and numbers, Sieg had thrown Shana off balance and used his Legions to draw her straight in to his finishing move.

The fiery-haired girl was hit by the full brunt of the shockwave.

As though she was punched by some powerful force, Shana lost control entirely and rolled across the ground.

Of course, she eventually came to a stop.

Battered and bruised, but still in fighting condition, Shana opened her eyes which she had shut tight while being tossed around and immediately thought to retreat.

Though that was her plan, Sieg made sure she didn't even get a chance.

Before her eyes, laying on the ground in front of her, was a small, bulb-like Legion. Its abdomen swelled up to ridiculous levels like a pregnant spider.

Shana realized just a moment too late what the purpose of such a Legion was.

Her ear drums were suddenly assaulted by an unbearably loud noise, and her vision turned to nothing but a flash of white before slowly fading into black.

* * *

She heard footsteps. A muffled voice was speaking. Her eyes opened and her blurred vision struggled to focus on the man approaching her.

"That was a good performance... but in the end, it was rather pathetic. I didn't even have to use my strongest Legion, and I'm completely unharmed. I expected to win, but at the very least I was hoping you would put up more of a fight."

Sieg pointed the tip of his blade at Shana's neck.

Somewhere off to the side, Shana heard an explosion. It was faint due to her impaired hearing, but it was definitely there. It was unlikely Sieg hadn't noticed, so it seemed he'd chosen to ignore it.

"Well, I suppose now that you're so broken, there's no use in playing with you any longer. I'll go ahead and put you out of your misery."

Sieg raised his sword into the air, carefully aiming a strike at her throat.

"Your life ends here. Perhaps I'll see you in the afterlife." He scoffed. "Though it's not likely. I'm almost sure to be going to hell."

Sieg's blade came down in a perfect arc towards Shana's neck. As soon as the sharp end made contact, it would be over.

But suddenly, and without apparent cause, Sieg's entire body was forcefully blown to the side.

* * *

"Wh-what?"

Sieg quickly stood from his collapsed position on the ground of the arena.

Something had come from his side and knocked him to the ground.

That something was flying through the air as he watched, going back in the direction it had come from as though satisfied that its task had been completed.

Opposite Sieg, coming from a hole in the arena's wall, was a pair of figures.

One of them reached out and caught the L-shaped object as it came back, pocketing said item while casually scanning the area.

And then Sieg heard a voice.

"Why don't you handle this one, hero?" spat one of the figures, as if the word "hero" left a bad taste in their mouth. "I'll check and see that the other one isn't dead yet, so you make sure that suspicious-liking guy isn't hostile."

Sieg couldn't see the faces of the figures very well from that distance, but he could almost hear the smile in the speaker's voice.

"And if they are, go ahead and deal with them."

* * *

"And if they are, go ahead and deal with them."

The boy in the white tunic heard those words and nodded, as if to accept an order from a higher-up.

Without paying mind to anything else, he started off towards the tall man with the deep red hair.

"H-hey!" The man shouted. "W-who do you th-think you are! Get out of here! I'll kill you!"

The boy in the white tunic raised an eyebrow at the man almost questioningly. The boy's left hand held a blade decorated with some form of triangular symbol.

"That's it! I'm tired of dealing with this shit! I'll use my trump card and put an end to all of you now!"

As the man spoke, a massive amount of energy gathered behind him. In an intense flash of light, a strangely-colored angelic creature appeared in a stance of servitude.

"Th-Thanatos!" shouted the angry man. "Kill these b-bastards!"

As if in conformation, the angelic being spread its wings and suddenly gained a huge amount of altitude. In mid-air, the creature balled up and began spinning like a turbine while gathering a nearly inane level of power for its ultimate attack.

The angel appeared to teleport, but in reality, it was moving too quickly to be seen.

It stopped directly in front of the boy in the tunic before pistoning forwards, releasing all of its energy into that one attack that was sure to pulverize its enemy with a single hit.

However...

Without hesitation, the boy in the tunic swung his blade upwards at an angle, striking the creature directly in between its wings.

At the same time, said blade began to glow an incredibly bright color that could not be described with mere words.

With that one concentrated strike, the blade cut straight through Thanatos.

The creature screamed before exploding into a billion, nearly microscopic fragments that fell to the ground with a shattering noise.

The incredibly powerful creature with both angelic and demonic properties, the inanely powerful Legion that killed anything with one hit, the invincible and undefeated creature that had beaten so many enemies before had been destroyed beyond repair with a single strike.

The man with the red hair carried an expression of pure shock as the boy in the white tunic stood unfettered before him.

"But... how..."

Sieg collapsed to his knees.

"Th-Thanatos! Thanatos, come back! Thanatos, Thanatos!... after all this time... can you really be beaten so easily?!"

For a small amount of time, the man's words dissolved into incomprehensible gibberish. Shortly afterward, he began to cry like a child who had dropped their ice cream.

And still the boy in the tunic stood still, watching him with little to no emotion.

After what seemed like hours, the man stopped sobbing and clambered to his feet.

Summoning a claw-like Legion below him, the man launched himself into the air, landing smoothly atop one of the stone walls of the arena. Shortly afterward, a second claw appeared below the Thanatos shards, scooping them all up and sinking back into the ground before reappearing next to the man atop the wall.

"I'll... I'll kill you for what you've done to Thanatos! Don't forget that! I'll definitely kill you!" the red-haired man shouted at the boy in the white tunic.

After saying that, the man unhesitatingly jumped off of the wall, presumably making his escape.

Yet still the boy in the tunic stood, expressionlessly watching the wall for a time before turning back to his ally, who was waiting for the collapsed girl to wake.

Something was definitely wrong with the natural balance of things. Somehow, for some reason, the realities of certain individuals had been suddenly and irregularly crossed.

Nothing made sense, but at the very least, they were not alone in their strife.

Perhaps, with a bit of time and some persistent investigation, they could find out why their paths had been so forcefully crossed over.

* * *

"It's just no use!" Sieg hurled his blade across the small shack, causing splinters to fly off the wall as it stuck there. "No matter what I do, I can't get this many fragments to come together! What am I supposed to _**do**_!?" In his rage, he swept his arms out to his sides. The action caused several bottles of various beverages to fall onto the ground, none of which shattered due to landing on a mattress laid out on the ground.

"I just... can't... do it." With all his will to continue swept cleanly from his heart, Sieg collapsed to the ground on his knees. "I simply can't fix it..."

"_But I can._"

A female voice suddenly spoke from inside the shack.

Sieg looked up, grabbing his sword out of the wall behind him as he did. A look of caution was on his face.

"_Don't even try it. Even if I meant you harm, you wouldn't be able to do anything from there,_" the voice continued.

Though it was at first a regular female voice, one could tell there was something off about it simply by listening closely enough.

Rather than sounding merely female, it also sounded like that of a robot or an AI. Or rather, the voice sounded just human enough that one might mistake it for a person attempting to sound like an AI.

"_I have a request. If you accept, your Legion will be quickly repaired – and stronger than ever._" The voice spoke smoothly, though it had the slightest bit of a condescending tone.

"What do you want, then?" Sieg asked without hesitation as he brought himself to hit feet.

"_One of our test subjects is in critical condition after his very first test. Do not be mistaken, he is extremely powerful. His loss was merely a fluke on the part of the other subject._" The voice spoke in such a way that one could not even hope to tell if what she was saying was a lie or not. "_We wish to merge your 'Thanatos' with our prime test subject, codenamed "Zeus". To repeat my earlier statement: If you accept, your Legion will be … stronger than ever._"

Sieg stood still for a moment, twirling the request around in his head.

After what seemed like an hour or two, he responded.

"Yeah... alright. As long as I can get Thanatos back."

The patiently waiting voice responded almost immediately.

"_Good. We'll have a representative come to pick you and your Legion up shortly. We'll have it ready for use within a week._" The voice paused for a moment in a manner that made one imagine the woman speaking to be pursing her lips. "_And in the meantime..._"

"_Maybe we can perform some tests._"

* * *

**Stop with that stupid grin on your face. It's annoying. If you're finished reading then get out of here. Geez. ...Though, perhaps leave a review on the way out. Maybe I'll read it or something, I dunno. Probably, if I ever get bored enough.**


End file.
